HI,

I have an 86 with climate control. I can hear my fan running pretty good but I don't seem to get a lot of air out of the floor vents. I can press bi-level and a lot comes out of the top vents.
Is there a diagram of the vent system? I just want to see if everything is in the correct position.
thanks

 

You probably have a vacuum leak. The supply vacuum from the engine should be what the engine vacuum is. Usually, the defrost position is the "at rest" position. If the supply is good, you might have a leak at the selector vacuum switch, which is obsolete from Delco and from Chevy. I know, because my 86 has similar problems. I found one in a wrecking yard.